Lathe



May 15, 1928. Y 1,670,139

' F. B. COCKBURN LATHE Filed May 8,: 1925 4 Sheets-Sheet 1 @11 WW1/y WM @Noruega May 15, 192s.v

F. B. COCKBURN i LATHE Filed vmay e. 1925l se bed.

Patented may l5, 1223.

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FRANCIS B. COCKBURN, Fl CINCINNATI, OHIO, ASSIGNOR TO THE LODGE &. SHIRLEY MACHINE TOOL COMPANY., OF CINCINNATI, OHIO, A CORPORTIN' @E GEIQ?.

LATER application mea may e, laas. serial no. 28,936.

This invention relates toimprovements in lathes and in particularV to the transmission forv the spindle employing a cone pulley and' belt drive' and in mounting the transmission a including an electric motor within a hollowleg beneath the headstock en d of the legproducing a /machine tool especially adaptable for. toolroom work to the elimination of. overhead belts and countershaft of the necessary transmission mechanism beneath( the headstock of the lathe, utilizing the weight thereof to obtain the greatest possible stability to machine and freedom H from vibration, and providing a machine organization with the transmission as a part of the machine, -in compact arrangement, and

vhoused within the machine frame structure.

l Another object is to mount the driving mechanism vand electrical equipment therefor, including a motor for transmitting a belt, upon a hinged base or platform in such manner as to utilize the weight of theA parts to apply tension to the belt, together with mechanism for positively swinging the platform to take its weight off of the belt, releasingv the belt tension primarily for shifting the belts from one cone pulley step l'to another. Another object is to provide an improved single piece belt shifter of simple construction by the use of which shifting of the belt can be easily and simply accomplished without undue wear of the belt.

Another object. of the invention-is to' provide abelt shifter asa single member engaging respectively the approach or driving and return runs Vof the belt, and at a relative iedge side thereof one in advance of the other ce in an order according to the direction of shift, whereby the belt can be shifted, when in a slack condition, onto a smaller stepor diameter of one pulley before advancing the same onto a larger step or diameter of as the other pulley which the belt connects..

Other objects and certain advantages will be more fullyset forth in the description 0f the accompanying drawings forminga part of this application, in which:

Figure 1 is an endsection showing myv invention applied to a'lathe of the cone head t pe.A A .yFigure 2 is a section at-right angles to Figure 41,taken through the -leg unit-l and An object of the invention is to place all Figure 3 is a plan section of the leg on line 3 3, of Fig. 1, showing'the mechanism supported therein and thereby'.v

Figure l is a side elevation at the head end ofa cone head latheshowing the unit in place.

Figure 5 is a section on line 5;-5, of Fig. 2, illustrating the construction of idler pulleyl for the belt.

Figure 6 is a section on line 6-6, of Fig.. 3, illustrating the structure of the tension relieving toggle.

The drawings illustrate only the headstock end of the lathe, with a headstock of conventional form with a cone` pulley drive for the spindle, the belt for the spindle pulley exs tending downwardly through the lathe bed and into the hollow leg of the machine and connecting with a pulley of the transmission mechanism including an electric motor supported and housed` within the leg. l

Referring .to the drawings llindicates the' lathe bed of the usual hollow form, so as to provide a passage 2.' therethrough, beneath` the headstock for the belt,.and 'space for an idler pulley 3 for the belt andan upper arm of va belt shifter, the idler pulley and belt tion ofthe leg 4.

The headstock- 6 is mounted upon lthe bed anA 'shifter beingmounted within the upper 'porways 7, in the usual manner and has a spin dle ,84, carrying a conc pulley 9 keyed thereto. The cone lies over the opening' or Apassage 2 in such position that the belt B engaged thereover leads downwardly through the bed of the latheY into the hollow Ysupporting leg.

The leg is preferably formed as shown and v is of box-like construction, comprising-the lower. large. substantially rectangular portion 10, and an upper smaller rectangular portion 11. This upper portion 11 has an internal marginal ange 12 through whichbolts 13 extend securing the leg t'o the lathe bed. The leg opens at its upper side into the passage '2, thus permitting the belt B,

ldisposed about the -upper cone pulley 9 toextendodownwa'rdly into the lower portion of the leg.- One runof the belt isf engaged againstl the idler pulley 3 which is rotatably 'mounted in thevertically disposed frame 15" having oppositely disposed, elongated sides, the lower ends-of which arejraversed byi-a horizontally disposed rod '16, vupon which the frame is thus pvotally mounted; for a slight swinging movement. The idler 3`is mounted upon a hollow axial shaft 17 the bore forming an oil reservoir to which oil is fed through an elbow and cup 18, extending freely through a slot in the leg wall outwardly from-the end of the shaft and in communication with its bore. The oil iS conducted to the bearings through suitable openings 19, (see Fig. The pulley frame extends upwardly within the opening of the bed, is .supported by the leg as a housing and support fora driving unit and is removable therewith as a part of the unit.

including the motor for operating the spin-v dle cone pulley. The hinge action of the plate is vherein obtained by a pair of trunnions respectively 25, 26, (see Figs. 2 and 3).

These trunnions have substantially the formA of bolts vor pins respectively extending inwardly from the opposite side walls of the leg and into sockets or bores 27, 28, in op: posite edge or end faces of the plate. .These pins are counterturned, (see Fig.` 2), to provide shoulders 29, 30, respectively forl pre- 'venting lateral movement of the plate,.and

for limiting the inward travel ofl the trunnions when .screwed into position, the said the leg. The lever is -fpurpose to be hereinafter disclosedv` The plate is thus pivotally or horizontally i plate and trunnions being threaded. as at 31, and also headed, for turning by wrench.

'The plate 1s,4 slotted inwardly from its edge as at 32 at right angles to the bore 28, .and the pin 26 traverses one end of a lever 35, as a pivot therefor, the lever extending freely through a slot 36in the side wall of broadened and terminally, transversely, cylindrically formed provide a foot or hand engaging portion 37 by which the lever may be` rocked for a connected at opposite parallel edges, and adjacent one side, with the greater portion of' beyond its pivotal axis andv in this instance 'in a direction trans-y versely of the lathe bed, thus providing ai the plate extending treadle-like device.

- Journaled upon the upper side of the otal axis, and parallel with said axis, and 'with' the headstock spindle, is a shaft 40 held at one extremity ina bearing 41 and adjacent the opposite extremity-.in `a bearing 42 beyond the outer side' of whichit projects'.v

The shaft is castellated, and removablyengaged with the vcastellations is a gear 45 as a change gear. Midway between the bearat that side farthest-from itspivings 41, 42, is keyed a driving cone pulley 50, in this instance having three steps corresponding in number to those'` ofthe headstock cone pulley 9 and-reversely related to those steps ofthe upper pulley in the usual manner, with the belt B connecting. the two pulleys as shown. Mounted also upon the upper side of the hinge plate adjacent 'the` conepulley is a motor 51 its major portion extending away from the pivotal axis of the plate toward the free end of the plate.

This motor may be of any preferred type,

and the electrical connections are not shown.

The motor has a drive pinion 52 meshing lwith the gear 53 keyed to a shaft 54 journaled in bearings 42, v55, attached to the plate. The opposite end of this shaft is castellated and has removably engaged with the castellations a gear 56 as a change gear meshing. with the gearl 45, these two gears forming a change gear train, thel gears of which may be changed or -interchanged t0 obtain corresponding speed change between the driving motor and the driving cone. All the supporting bearings as well as the plate which supports the motorlare removablyl attached to the plate, and therefore,

may be conveniently removed. A hinged door 60 closes an opening 61 in the vertical wall of'fthe leg, the door having a suitable hand operated latch for closing and locking the same, thus permitting access to the change gears 45, 56. ccess to or removalof the motor may be obtained through the` opening 65 closed by the door 6,6.

The hinged plate withits mountings ar-v ranged at one end at the same side of the pivotal" axis, providesa weighted swinging element for applying a tension lon the-belt B. This driving unit acts as abelt tightener,`a`nd means. is further provided for forcibly. raising the same manually from a point outside theileg for releasing the belt 'Y tension particularly when the belt is tol be shifted. To this end a toggle device is provided for forcibly lifting the plate and load ilo thereon. one member 70 of which is pivoted v as at 71' between the ears of'the yoke 72 having a screw threaded vextension traversing a vertical wall of the latch, the yoke being clamped in 1position by a nut 73. The swinging element 7() is herein of substantially triangular configuration'.` .At the lower en d of the element 70 is pivoted as at 75 a link 76, the opposite end of which is pivoted as'at pivoted upon the trunnion 26.

77 to the lever 35 which is Pivoted to the element 70, as at'80, interj 'mediate lthe pivots 71, 75, are a pair of links 81 the lower ends of which are pivoted as at 82 at opposite sides of the block 83, attached to the plate by a bolt, and nuts, asbest shown in 6. The upper end of the links also lie at opposite sides of the element 70.

Normally the center of thepin `80 lies'slightly to one side ofthe line drawn through the 71, 82 and in a direction to which the element very slight movement centers of the pins away from the Wall 7() is attached.l B'y .of the lever 32 downwardly the plate is same. vThe plate raising device may in some lever has afsuitable l one above the other.

there-to,

'an elongated body securedby a set "freely traversed Each loop 'is'elongated in direction of shift l parallel lanes,l

instances be dispensed with, or other. equivalent means for raising the plate may be conve'niently'used.

A belt shifter' is incorporated as apart of the lbelt unit, and is mounted upon and within the `unit for horizontal translation, in this instance, in a direction longitudinally of the bed, and of the axes of the driving and driven cone pulleys. The shifter is I mounted on a rod 100 which traverses and 1S slidable in opposite4 side walls of the upper section 11 of the leg, and projects therebeyondat both sides. One end overlies the top" horizontal portion of 10 of-the leg and has 'a block 101 .pinned the block being grooved on its upper side as at 102 and havingA slidably engaged therewithja pin 103, held at the outer `end of onev arm of 'the-shifter lever 104, pivoted uponfthe to of the leg for oscillation 'in a horizontalp ane. -The'outer end of the handle which is accessi- -ble from the front side of the lathe whereby the shifter rod may be translated in any deree.

g My improved shifter member comprises .portion including two arms 110, 111, the member being bored as at 112 intermediate its ends 'for the reception of 'a slide bar to which the'member is Iixedly screw; Each arm has at its extremity a ring-like loop ll'adapted to be by one run of the belt.

or crosswxse of t e belt. The loops lie 1in zontal p anes, and substantially vertically vThe length of the slots is greater than the width of the belt, see Figure A2', and-said slots extend beyond-lts edge In reverse directions lat relatively opposite edges of the belt,

whereby when the shifter is translated in either direction one edge of one run of the belt will be engaged before the opposite edge ofthe other run of the belt. Y

:the lower section pulley, a

vhinged pivot, a

in this installation-in hori-l one loop engagesone edge of one run of theA belt to release one loop from -its cone step before the' .opposite edge of the other runis engaged ,to bring the other loop over the corresponding step of theother pulley.

The arm 110 is offsetA in direction of shift,-

see Figure 2, toprovide clearance about'the adjacent run whichis operated by the loop at the' end olithe arm 11'1. Both arms are also terminally bent in the same direction and in a plane at' 'rightl an of the offset ofthe arm, see-PFigure 1, so that the idler pulley'B' .may be disposed between the vertically aligned loops or rings to bring the belt runs nearerone another and thus compactly dispose'the guide` and shifter elements, a-nd permit .the shifter member to be translated' without interference with the guide pulley 3. L e

Having described my invention, I claim: A cone head lathe including a bed, a heads tock and bed supportlingleg adjacent and beneath the p ate within the leg horizontally disposed and ladapted for limitedvertical swinging movedriving pulley jours f ment, a second cone naled upon the plate at. one sideV ofthe belt transmittably connecting the lpulleys and extending through the bed, amotor upon the plate in vdriving con nection Wlth the second pulley, and means vfor forciblyraising the plate for relieving said means comprisingtension of the-belt, a link pivoted at one end to the sidewall of the leg above theV free end of the plate, a second link pivoted at an intermediate point of the first 'link and at its lower `end to the plate at .its unsu portedside, the intermediate pivot of t e three being disaligned from' the others in direction away from the wall when the tension is being applied to the belt, and means for forcibly drawing the first link in a direction away om the'wall. Ill-witness whereof, I hereunto subscribe my name. i

e FRANCIS lB. COCKBURN.l

les to the plane a cone pulley therefor, a hollow hinged at one side to and l v 

